Exciton dynamics in paracyclophane coupled dimers

Understanding and manipulating through-space electronic communication within aggregates of organic fragments with delocalized bonding structures can impact a range of nanotechnology applications. However, interrogating aggregates of this type has encountered multiple difficulties in the past, ranging from heterogeneity of environments in the solid to the ill-defined geometry of intermolecular contacts in solution. These difficulties are circumvented by designing aggregates which contain [2.2]paracyclophane contacts among molecular units with well-defined architectures and dimensions. These offer excellent control over the distance and relative orientation of the participating units and provide a model system for detailed examination of the molecular structure-function relationship of conducting polymeric materials. We present a comparative experimental and theoretical study of a model complex consisting of two (oligo)phenylenevinylene chromophores that are strongly coupled through a paracyclophane junction. Ultrafast pump-probe anisotropy measurements are compared with numerical simulations to investigate the nature of exciton dynamics in strongly coupled chromophores.